Motor units

• Motor unit

  A motor unit consists of a motor neuron and a number of muscle fibres.
• Motor neurones are specialised cells which transmit nerve impulses to a group of muscle fibre.
• The point where the axons motor end plates meet the muscle fibres is called the neuromuscular junction.
• Muscles can only contract When stimulated by an electrical impulse.
• Impulses are sent from the CNS and travel down the extending axon which connects to the motor end plates
• Action potential refers to a positive electrical charge inside the motor unit , which conducts the nerve impulse down the neuron into the muscle fibre.